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The Mammals of Texas -
Online Edition
Short-finned Pilot Whale
Order
Cetacea : Family Delphinidae : Globicephala
macrorhynchus Gray
Description. A rather large, black
delphinid with globose head, no beak, and a bulbous
swelling on the forehead in adults; dorsal fin far
forward on body, beginning about on plane with back of
pectoral fins; pectoral fins long and narrow, about 1/5
of body length; mouth oblique; teeth large, about 10 mm
in diameter, 20 mm high, conical, incurved, placed only
in anterior part of jaw, and numbering 8-10 in each tooth
row. External measurements: total length of male, 4.72 m;
tip of snout to dorsal fin, 1.37 m; tip of snout to
pectoral fin, 838 mm; length of pectoral fin, 864 mm;
breadth of flukes, 1.07 m.
Distribution in Texas. Common
inhabitants of offshore tropical, subtropical, and warm
temperate waters of the world. They are common in the
Gulf of Mexico and numerous stranding and sighting
records are available from Texas.
Habits. Short-finned pilot
whales may congregate in large numbers offshore
schools of several hundred have been observed but
group size usually ranges from 10 to 60. They are seen
inshore at infrequent intervals and occasionally become
stranded by severe storms. In fact, these are among the
most frequently stranded of cetaceans, and often mass
strand. These dolphins have mass stranded 15 times in the
Gulf of Mexico, although none of these events occurred in
Texas. Pilot whales are highly communicative and make a
variety of sounds, including noises described as
"squealing, whistling, loud smacking, whining, and
snores." They probably are excellent echolocators.
The food habits of pilot whales are not
well known. In the wild they feed on squid and fish; a
captive whale consumed 20 kg of squid per day. This
particular whale showed no interest in the fish fed to
dolphins in the same tank.
Breeding and calving take place in
winter. Gestation lasts about 12 months. Calves are about
1.4 m long at birth and weigh approximately 59 kg.
Females are believed to give birth only once every three
years.
Illustration credit: Pieter
A. Folkens.
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